By: Kristen Falik
How do they happen?
COVID-19 is caused by the SARS-CoV-2 coronavirus. Which is a tiny particle that is slightly longer than the length of RNA (genetic code) and is wrapped in a molecular, spiky coat. When coronavirus infects a human cell, it replicates itself thousands of times. This is done very quickly and when it replicates it is at risk for a mistake in its genetic code, called a mutation. These mutations can be small and irrelevant to the virus and affecting no change. It can also be a mutation that puts the virus at a disadvantage. There are so many SARS-CoV-2 variants that we haven’t heard about since they don’t affect the performance of the virus so they are not as persistent in the population. But some variants that we know more about are caused by mutations that give the virus an advantage. This can include making the virus better at infecting people or evading our immune systems. These copies of the coronavirus can be possibly mutated and then they go out and look for new hosts once it leaves the body, possibly affecting others with the variants. Because there are so many people being infected every day with the virus, there is an increase in the likelihood of mutations causing variants.
Why are they a problem?
Here’s some background information to know: If you have done any evolution in biology then you may have heard of the term natural selection. Natural selection is the selection of advantageous traits in individuals that increase their chance of survival increasing their chance of reproducing. This is similar to what happens in viruses because some mutations may have a decreased ability to spread easily and be as invading on the human cells that they do not pass on to new hosts and continue to duplicate so they are not as frequent in the population. Whereas the mutations that are advantageous that have more of an effect on humans and spread easily are potentially selected for which increased their chance of duplicating and being more frequent in the population.
So, once an advantageous genetic change in the virus appears those with the advantage become the dominant strain quickly. This is demonstrated in the B.1.1.7 variant because it has a cluster of mutations that affect its spike protein which makes it be able to spread more easily. This is why in the news you may have seen information about variants being more serious and spreading easily because the virus is following evolutionary pressure for it to keep changes that may help evade immune responses and/or pass on to more hosts to survive for longer.
Will vaccines work on the variants?
Researchers are saying it’s hard to say at this time. COVID-19 vaccines train our immune system to fight off the spike proteins that are on the surface of the virus. There is concern that new variants with changes to the spike protein that help them to evade immune responses may have the potential to render vaccines. So far, research has shown that the vaccines are still effective for fighting certain variants they have tested them with but more is still needed to discover this.
Scientists are starting to investigate the possible impact of some potential future mutations in their laboratories. Many vaccine producers are working on making updated versions of their vaccines to protect against new variants. Additionally, vaccine companies are working on boosters of the vaccine for those that were vaccinated in the very early stages of vaccine rollout to protect against new variants. If variants continue to arise, it is likely that regular boosters are needed to ensure immunity.
With that being said, make sure to continue to stay safe and follow social distancing and other guidelines in your area to protect others. This is needed even if you are already vaccinated to prevent the spread of the virus and its variants.
To learn more visit: What are COVID-19 variants, where do they come from, and why do they matter? (joinzoe.com)
